Multidigit shifting device



'Jn'. 21.)',V 1955 F. E. HAMILTON ETAL MULTIDIGIT SHIFTING VDEVICE Original Filed Jan. 19, 194e 7 Sheets-Sheet l all) ATTORNEY Jan. 25, 1955 F. E. HAMILTON ETAL 2,700,502

MULTIDIGIT SHIFTING DEVICE Original Filed Jan. 19, 1949 7 Sheets-Sheet 2 F. E. HAMILTON R; E. SE EBER,J`R

ATTORNEY Jan. 25, 1955 F. E. HAMILTON ErAL 2,700,502

MULTIDIGIT SHIFTING DEVICE Original Filed Jan. 19, 1949 7 Sheets-Sheet 3 l .S 'RII ATTORNEY Jan. 25, 1955 F. E. HAMILTON ETAL. 2,700,502

MULTIDIGIT SHIFTING DEVICE 7 Sheets-Sheet 4 Original FiledA gan. 19, 1949 lfm-Im m .rm-Im EN INVENTORS F. E. HAMILTON R. E. SEEBER,JR.

ATTORNEY Jan., 25, 1955 F. E. HAMILTON ETAL 2,700,502

' MULTIDIGIT SHIFTINQ DEVICE Original Filed Jan. 19, 1949 7 She-ets-Sheet 5 I INVENToRs .1ll E @i E E. HAMILTON x R. R. SEEBER,JR.

ATTORNEY Jan 25, 1955 F. E. HAMlLToN ETAL 2,700,502

MULTIDIGIT SHIFTING DEVICE Original Filed Jan. 19, 1949 7 Sheets-Sheet 6 Jan. 25, 1955 F. E, HAMILTON ETAL 2,700,502

MULTIDIGIT sl-IIFTINGv DEVICE:

Grignal Filed Jan. 19, 1949 7 Sheets-Sheet '7 S//c LI f I SHE INVENTORS TTORNEY United States Patent() MULTIDIGIT SHIFTING DEVICE Francis E. Hamilton, Binghamton, and Robert R. Seeber,

Jr., New York, N. Y., assignors to Intematonal Business Machines Corporation, New York, N. Y., a corporation of New York Original application January 19, 1949, Serial No. 71,642,

now Patent No. 2,636,672, dated April 28, 1953. Divided and this application March 27, 1952, Serial No. 278,876

27 Claims. (Cl. 23S-61) The present invention relates to electronic computers and more specifically to denominational shift means commonly referred to as column shift means for electronic computers and is a division of the copending application of Hamilton et al., Serial No. 71,642, tiled January 19, 1949, now Patent 2,636,672 issued April 28, 1953.

One of the objects of the present invention is to provide electronic shift means for producing shift in either of two directions.

Another object is to provide electronic shift means in combination with means for measuring and regulating the number of steps of shift.

A further object is to provide in combination with electronic shift means, means for determining selectively the number of steps of shift, including zero steps of shift.

Another object is to provide, in combination, electronic shift means and means for determining both the direction and amounts of shift.

A further object is to .provide electronic shift means for producing shift of an entry in one order of a register to another order, each order comprising means for representing any digit of any radix.

Still another object is .to provide electronic shift means for producing shift of an entry in one order of a register to another order, each order comprising a .plurality of means for representing any digit in any radix.

Another object is to provide selective `shift ymeans ,for producing a shift of Van entry in any order of a register to another order, each order comprising means for .representing any digit by a permutation of elements less in number than the radix employed.

A further object is to provide electronic column -shift means for shifting all digit values in a plural 'order register in one operation.

Still another yobject is .to provide means for producing column shift from one order lof a register to another-order and also producing a still further indication of the 'respective values of the respective orders.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way -of examples, the principle of the invention and the best mode, which has been contemplated, `o-f applying that principle.

In the drawings:

Fig. l is a detailed wiring diagram of a typical trigger circuit employed in the denominational shift means.

Fig. 2 is a block symbol 'of the device of Fig. l.

Fig. 3 is a detailed wiring diagram of a triode of 'the invention.

Fig. 4 is a block symbol of the device of Fig. 3 and -also is representative of a te'trode.

Fig. 5 is a detailed Wiring diagram of .a tetrode employed in the invention.

Fig. 6 is a detailed wiring diagram of a pentode em ployed in the invention.

Fig. 7 is a block diagram of ythe device of Fig. 6.

Fig. 8 is a detailed wiring diagram of a lock .couple employed in the invention.

Fig. 9 is a block diagram `of the device of Fig. l8.

Fig. 10 is a detailed wiring vdia-gram of a cancel circuit employed in the invention.

Fig. 11 is a block diagram of the device of fFig. l0 and ice further illustrates connections of the cancel circuit output to triggers to be cancelled.

Fig. 12 is a block diagram of one column of the denominational shift unit.

Fig. 13 is a block diagram of the complete denominational shift device.

Fig. 14 is a timing chart of operations occurring during a single step of denominational shift and;

Figs. 15a, 15b and 15c taken together, one placed above the other, comprise a'block wiring diagram of the internal commutator and descending counter for controlling the denominational shift means of kthe invention.

Before proceeding to the detailed description of the device, a brief explanation of the manner in which the description will be developed will rst be given.

Figs. 1 to 11, inclusive, illustrate the details and block representations of all the elements of circuitry employed in the novel denominational shift means. Fig. 12 is a complete diagram of one order of .the novel shift means and including the input to and the output from the shift means, in which the respective elements of circuitry are indicated by the blocks, covered in detail in Figs. 1 to 1l. Fig. 13 indicates the manner in which several columns of the shift means, as illustrated in Fig. l2, are connected together to comprise the complete shift device. Fig. 14 is a timing diagram which, taken together with drawings 15a, 15b and 15C, illustrate, in block diagram and by timing, the internal commutator and vdescending counter operation as employed in controlling shift either to the right or to the left and for a preselected number of steps.

VBefore proceeding to the description of the -novel shift means, as illustrated in Figs. 12, 13, 14 and Figs. 15a, 15b and 15C, the circuit elements of Figs. 1 to l1, inclusive, will be described in detail. Subsequent to such description, of the circuitry of the various elements comprising the blocks .in the diagrams of the shift device, it will be assumed that the operation of the circuits Within the blocks, as illustrated in Figs. l2, 13, `14 and Figs. 15a, 15b and 15C, will be understood. The particular circuitry will now be described.

General circuit data A source of supply (not shown) is provided for `the voltage lines running through the various circuits. This 'source supplies the voltages shown in the various figures. The line C is a `cancel bias line, the purpose of which will be explained in the subsequent descriptions of the `trigger `and cancel circuit. The triodes used in the circuits are ofthe 6SN7 rtype and may be the halves of twin tubes 12SN7. The tetrodes, which are used mainly as power amplifiers, are of the 25L6 type. The pentodes are generally ofthe 6SK7 type. In some instances 6Sl7 tubes are used.

Resistance values shown are in megohms and capacitance values in micromicrofarads, unless otherwiseindicated.

Referring to Fig. 3 which is the detailed circuit of a 'triode as employed in the novel shift device, the cathode terminal k of the triode is shown as connected to ground or 0 v. line. The anode terminal an is connected vthrough a resistor to the v. line. The value of the resistor for an individually operated triode is .generally .02 meg. Operation of the triode is generally effected by applying a pulse from thev output of vanother tube to its input terminal gi. This input terminal leads to a voltage divider which is tapped by a connection to the grid of the triode. The voltage divider terminates at the 100 v. line. That portion of the voltage divider, between the grid and the 100 v. line, generally has a resistance value of .'47 meg. and lthe other por-tion of the voltage divider, in that event, has a resistance value of .5l meg. In some instances, where it is desired to reduce ythe time constant or 'to provide for a smaller grid leak impedance, the resistance values of the upper and lower portions (as shown) of the voltage divider are .24 and .22. The input potential -to the voltage divider generally has a swing from about 50 v. to l5() v. although in extreme instances the input voltage may descend to 'about l5 v. It may be seen from Fig. 3 that the triode is normally biased 'to cut-'olf when the 'input potential to the voltage divider is at its lower value. When the input voltage rises to its upper value, then the grid potential is driven above cut-o and the tube conducts. Where it is required to increase the rapidity of response to an input pulse, the upper portion of the voltage divider is shunted by a capacitor, which is generally 50 mmf. The anode resistor may be tapped at a suitable point anr for connection to an element to be operated by the output of the triode. It is to be understood that constants given are merely illustrative and that other appropriate constants may be used.

Fig. 5 is the detailed wiring diagram of a tetrode and indicates appropriate values for the circuit elements thereof. The screen grid of the tetrode is generally connected by a .005 meg. resistor to the +70 v. line. Operation of the cetrode is eiected in the same general manner as the tr1o e.

Fig. 4 is a block diagram representing either the triode or the tetrode. The cathode terminal k in the block diagram will be omitted except where it is necessary to an understanding of the operation of the tube. It is to be understood that tetrodes Will be used wherever power ampliiication is a prime requisite.

Fig. 6 is the detailed Wiring diagram of a pentode. I

The screen grid is generally connected directly to the +70 v. line. Suitable values for the anode resistor and the portions of the voltage dividers connected to the control grid and the suppressor are indicated. The operation of the control grid is eiected similarly to the operation of the control grid of the triode and the input terminal for that voltage divider which is tapped by the control grid is marked gi. Another input terminal si is connected through a resistor generally having a value of .33 meg. to the suppressor grid and the suppressor i grid is connected through a resistor of .68 meg. to the 250 V. line. The input potential to the terminal si also varies from about 50 v. to 150 v., in general, although as previously indicated in discussing the input potential the grid of the triode shown in Fig. 3 through a coupling capacitor, the resistor, shown in this figure as shunting the capacitor, is omitted. In some instances a tube may be used as a cathode follower in which case suitable resistance will be provided between the cathode of the tube and a voltage supply line. A tube may be biased normally to cut-off or to conductive condition. Where it is necessary to clarication, the normally conductive tube will be identified by the small letter x placed adjacent the symbol for the tube, for example, as shown adjacent the right hand triode 10 of Fig. 1.

Elements in a block diagram circuit may be identied by a particular reference character, taken together with a general reference legend for the circuit, which legend may be the gure number or a capital letter or letters. Where an element is thus identified in an item of the description, subsequent mention of elements of the same circuit will be made without reference to the general identifying legend unless mention of another circuit figure intervenes or unless it is necessary to clarification.

T he trigger One of the fundamental elements of the circuits is a double-stability electronic trigger circuit which will be called simply a trigger. The general form of this trigger is shown in Fig. 1. Typical constants are indicated for the trigger but it is understood that other suitable constants may be used. This trigger is fully discussed in Application Serial No. 569,992 of Palmer and Phelps, tiled December 27, 1944, now Patent 2,536,955. Briey, it includes two retroactively coupled tubes 10 and 14. In one stable state of the trigger, tube 10 is conductive and its anode terminal f is at about 50 v., while tube 14 is i non-conductive and its anode terminal c at about 150 v.

In the opposite stable state of the trigger, tube 10 is nonconductive and point f is about 150 v. while tube 14 is conductive and point c at about 50 v. Upon reversal of the trigger from one stable state to the other, there is to the terminal g, the input potential may drop to as low as l5 v. It is seen from Fig. 6 that when the input potential on either terminal si or gi is at its low value, the pentode is cut oit'. Both the input potentials to terminals si and gz' must be at their upper levels in order to render the pentode conductive. Fig. 7 is the block diagram representing the pentode of Fig. 6.

The output potentials at the terminals any of the triode and the pentode may be taken as having a lower value of approximately 40 to 50 v. when the tube is conductive. However, it is quite possible for the potential at the anode of a pentode to drop to as low as 15 v. The anode resistor will be tapped at a point such as to provide the necessary working potential for an element to be controlled by the tube. It may be stated that where the output of the tube is to be applied to both input terminals a and h of a trigger (see Fig. l), then the tap point am is generally the midpoint of the anode resistor. Where the output potential of a tube is to be applied to only one of the terminals a and h of a trigger, as described below, the point anr is generally connected through a .0075 meg. resistor to the +150 V. line and connected through a .012 resistor to the anode of the tube.

Fig. 8 shows the 12SN7 tube with both triode sections of the tube having their anodes connected to each other. The common anode resistor in such case generally has the value .051 meg. The inputs to the sections are separate so that each of the sections may be individually operated. This circuit may be referred to as a lock couple. Both of the tube sections must be cut oli` in order to allow the common anode line to attain its upper voltage level. If both tube sections are at cut-oli and one of the sections is then made conductive, the common anode potential generally will drop to about 50 v. Fig. 9 is the block symbol for the lock couple of Fig. 8.

The block symbols will be employed in the circuit diagrams of the machine. It may be mentioned that the impulses to the input terminals of the tubes may be applied through coupling capacitors which are of varying capacities depending on the desired pulse shape to be transmitted by the capacitor to the input terminal.

Where it is necessary to clarification, arrows will be used to indicate whether signals are coming in or going out of a circuit.

Where a coupling capacitor is used to transmit a pulse to a grid of a tube, the coupling capacitor is not shunted by a resistor. For instance, if a pulse is to be applied to a steep drop in potential or negative going impulse of about v. at the anode terminal of the previously non-conductive tube and a simultaneous rise in potential or positive going impulse of about +100 v. at the anode terminal of the other tube. Also, a negative impulse of about 50 v. appears at the midpoint d of the anode resistor 14r when the trigger is reversed from the status in which tube 14` is non-conductive to the status in which this tube is conductive. Also, upon return to its previous status in which tube 10 again is conductive, a negative impulse of about 50 v. appears at the midpoint e of the anode resistor 101'. It is characteristic of this trigger that it reacts sensitively to a negative impulse of suitable amplitude but is insensitive to a similarly applied positive impulse of like amplitude. In the present case, a negative impulse of about 40 v. applied to the trigger input terminal a or h is eliective to reverse the trigger, but a similarly applied positive pulse of the same amplitude is not etective to reverse the trigger. A negative impulse of about 50 v. applied concurrently to both a and h will be eifective to reverse the trigger but a positive impulse of the same amplitude and similarly applied will be ineiective. Reversal of the trigger, however, may be elected by directly impressing adequate positive potential (about v.) on the grid terminal of the non-conducting tube of the trigger. Where an impulse source is connected to only one of points a or h, the other point terminates at the +150 v. line, thus adding stability to the trigger.

Reversal of the trigger also may be effected by an auxiliary circuit operable to draw current though anode resistor 10r or 141 so as to depress the potential at the terminal c or f to about 50 v. Such auxiliary circuit may take the form of an auxiliary tube. For instance, in Fig. 3, a triode 10A is indicated as having its anode connectible to terminal f of tube 10. If tube 10A is rendered conductive, then it will force the potential at terminal j down to about 50 v., reversing the trigger to that status in which tube 10 is conducting or blocking reversal of the trigger from this status.

In some instances the trigger may omit the coupling capacitors 13a and 13b, these capacitors being essential as a rule only if it is desired to trip the trigger by applying impulses simultaneously to the points a and h.

It will be noted that in Fig. l, the grid resistor of normally at -100 v. potential, but in other instances aan@ where needed, the cancel line will Ybe connectedA to the grid resistor yof `tube ,14.r A positive cancel impulsewill be applied at a desired time to incline lotto to vincrease its potential to approximately ground potential. This will 'reset the trigger te that state in which the tube, connected to the cancel line through the grid resistor, is conductive. The reset status of ja trigger is denoted by the small letter x adjacent the tube which is `crmducting in the reset status, as for example the x adjacent tube '10 in Fig. 1

In some instances, the grid resistor terminal gr is connected to the -100 v. line through an auxiliary tube E. When this auxiliary tube is conductive it simply acts as a low impedance connection between the grid resistor and the 100 v. line and allows the` trigger to function in a normal manner. When the auxiliary tube E i's rendered non-conductive, its anode potential and. therefore 'the potential at the grid of the connected tube 14 rises above cut-'off potential and causes lthe trigger to assume the status in which tube 14 is conductive. The auxiliary v tube E may thus be used torever'se a trigger, The block symbol for the trigger is shown in Fig. 2. The terminals, shown in dotted lines, will be omitted in most instances, in order to simplify the drawings and will be Vshown only where they are utilized in controlling the trigger. The cancelled status of the trigger will be considered as its normal reset status and the trigger will be spoken of as being turned and returned or reversed and reset, it being understood that the reset or return is to its shown cacelled status.

Basic cancel circuit Fig. shows the basic cancel circuit operable to cancel a group of triggers. A plurality of such 'circuits are provided for various groups of triggers in the machine. The basic cancel circuit includes a normally cut off tube 75, a voltage regulator tube 76, and one orl a group of power tubes 77, depending on the power requirement. The output of 77 is connected to the cancel line 100C of a group of triggers. The^ constants ofthe cancel circuit are such that 77 is normallyconductive to sustain linel 100C at 100 v. The voltage of line 106C may uctuate slightly according to changes in the states of the connected triggers. These fluctuations are' counteracted through the action of the voltage regulator tube 76 Vand its circuit. For instance, if line 106C goes slightly more negative than 100 v1., it causes the voltage regulator tube to become proportionatelymore conductive so as to increase the negative bias on 77. As the negative bias on 77 increases, itsy Aoutput voltagemrises, increasing the voltage on line ljtOC- to -100 v. When it is desired to cancel or resetthe groupw'of triggers, va positive cancel signal is applied to tube 75 to make it conduct and thus negatively bias 77 to non-conductive condition. The line 100C thereupon rises to substantially cathode potential, so that the connected triggers are reset to the states indicated by the x marks.

Fig. 1l shows in block diagram the basic cancel circuit and also two methods employed by the cancel circuit to reset a trigger. According to one method, the Acancel circuit output 100C is connected to the terminal cc of a trigger (also see Fig. 1). According to the other method, the line 100C is connected to the ,grid ofan inverter tube I which serves, in the manner of tube 10A in Fig. l, to force a trigger to its reset statuslwhen the tube becomes conductive. Thus, when a positive cancel signal is applied to the input of the cancel circuit, its output line rises in potential and renders tube I conductive to reset the trigger.

l-Iaving described the details of circuitry of each of the circuit elements employed in the novel denominational shift device, the device itself will now be described with reference only to the respective block representations of the circuit elements.

The denominational shift device Fig. 12 shows in block form one order of lthe novel column shift device. Its purpose is to shift 'anar'nount a selected predetermined number of columns and selectively either to the right or the l'eft. The. multi-digit amount to be shifted is sent into the denominational 'shift unitk from the Internal In bus .column and delivered to the Internal Out bus column. The shift unit has `28 shift columns (Fig. 13) each one like thatdisclosed in'Fi'g. 12. Shift columns 1 to 28 are associated, respectively (Fig.

13.) with Internal bus columns 29 'to 2.

Each column (Fig. 12) of the denominational shift unit 'has a set of elements allotted to each 'of the four binary positions in the particular embodiment illustrated. T he pentodes IT1, ITZ, IT4, and ITS are the input tubes of a shift columnl and their Suppressors are coupled to buses 1, 2, 4, and 8, respectively, of a column of the Internal In bus column. The bits of the binary decimal terms of a digit are represented by increased potential selectively presentin the respective buses of an Internal In bus column. Therefore, tubes IT are selectively conditioned according to these bits of the binary decimal terms. Subsequent to conditioning of the tubes IT, a positive entry timing signal SHRI as shown, is applied to the control grids of the pentodes, rendering only the selectively conditioned tubes conductive. The anodes of IT1, `2, 4, and 8 are coupled to terminals c of triggers ASHl, ASHZ, ASH4, and ASHS, respectively. When a tube IT becomes conductive, it reverses the corresponding trigger ASH. A first negative cancel signal ACL is applied to points a of all the triggers ASH to reset only those which are not being held in turned state by conductive tubes IT. The signal ACL is produced concurrently with signal SHRI but is shorter and has a briefer effect, so that the triggers ASH, turned under control of signal SHRI, remain turned to store an entry. The turned triggers ASH apply increased potential to correspondingly numbered output lines SHO. As an example, 'assume the binary decimal bits 1 and 4, representing digit 5, have been applied to a shift column, conditioning, respectively, tubes IT1 and A4. The entry ysignal SHRl will render the conditioned tubes IT1 and IT4 conductive causing them to reverse the respective triggers ASHI and ASH4 only, which thereupon apply increased potential to the output lines SH01 and SHO4. As indicated diagrarnmaticallyin Fig. 13, the output lines SH01, SH02, SHO4, and SHO8, of each shift column, except the end columns 1 and 23, connect to the shift columns at the right and also at the left. The connection to the column at the right is to a set of input lines SHR while the connection to the 'column at the left is to a set of input lines SHL. The lines 'SHLL SHL2, SHL4, fand SHLS (Fig. 12) are coupled to the Suppressors of tubes FLSl, FLS2, FLS4, and FLSS, respectively. The respective lines SHR are coupled to the Suppressors of a similar set of tubes FRS. It is seen therefore that increased potentials on output lines SHO of a column are applied to the input lines ySHL `of the column at the left to condition its tubes FLS selectively and at the same time the increased potentials on Vthe lines SHO are applied to the input lines SHR Iof the column at the 'right to condition its Itubes FRS. The outputs *of both tubes FLS1 'and FRSl 'o'f`a shift column connect to point c of atrigg'er BSI-l1. Similarly, FLSZ 'and FRSZ are connected to BSI-I2; FLS4 and FRS4 are connected to BSH'l; 'and FLSS and FRSS are connected to BSHS.

After the application of the entry signal SHRI and cancel signal ACL to the denominational shift unit, as just described, we proceed to denominational shift, per se, by means of a negative cancel signal BCL which as shown (Fig. 12) is applied to reset all the triggers BSH, of which there are four for each column, to the condition as indicated. Next, after resetting triggers BSH, either selected one, or two positive signals RSH and LSH as shown, is applied to the denominational shii't unit, depending on whether the shift is to be effected towards the right or the left. Assuming that the shift is to be effected towards the right, the signal RSH is applied and it will 'render only the conditioned ones of the tubes FRS conductive which in turn reverse the vassociated triggersy BSH. If, instead, the shift is to be effected towards 'the left, then the signal LSH is applied and c auses the conditioned ones only of the tubes FLS to 'conduct so as to similarly reverse the associated triggers BSH. AS will now be understood, a digit entered in a shift column is ready to be shifted to the right or to the left but is permitted to shift only in one direction, depending on whether the left or right shift signal is applied to the denominational shift unit. Also, each intermediate shift column has applied to it, in the form 'of conditioning potential, a digit from the column at its right and also another digit from the column at its left but it is to be noted that iinally only one of these digits will be actually `shifted into the column. If the shift is to be to the right, then the digit shifted into a `column comes from the column t 'the llft While i'f the Shift iS t0 be 't0 'fh'e left, then the 7 digit cornes from the column at the right. The shifted digit, from the left or from the right, is manifested by the selective reversals of triggers BSHI, BSH2, BSH4, and BSHS which temporarily store the shifted digit. After the digit has been shifted into these triggers BSH, the triggers ASH, of each column, are again reset by a signal ACL, in preparation for receiving this shifted digit from the temporary storage triggers BSH of the same column. Only reversed triggers BSH condition related pentodes SHT. The signal following this last mentioned reset of triggers ASH, is, as shown, a positive signal SHE which renders only the conditioned ones of the tubes SHT conductive, to in turn selectively reverse the related triggers ASH. In this manner, a digit which has been shifted into a column is entered in its triggers ASH.

Briefly, in summarizing the operation so far, after the application of the digits of a number from the Internal In bus column to tubes IT of the associated shift column, those 'triggers ASH which do not have bits of signal applied thereto are reset by a cancel signal ACL while a signal SHRI causes the conditioned tubes IT to conduct and set the related triggers ASH according to the digit in the column. Triggers ASH, in each shift column, thereupon apply the digit to both the flanking shift columns. The denominational shift unit is now ready to perform one or more successive column shift steps. The subsequent sequence of signals in each shift step is summarized as follows:

1. The cancel signal BCL is applied to cause triggers BSH to be reset, preparing them to receive a shifted dlglt.

2. The shift signal RSH or the alternative shift signal LSH is applied to cause, either the right or left shifted digits, to be entered in triggers BSH. For a shift to the right, the signal RSH is applied and the digits shift into the columns at the right while for a shift to the left the signal LSH is applied and the digits shift into the columns at the left.

3. The cancel signal ACL is applied to clear the triggers ASH of each column, of the digits previously enteredfltO therein and now shifted to an adjacent column.

4. The signal SHE is applied to transfer the digit, shifted into a column, from its triggers BSH to its triggers ASH.

Each above sequence effects a single step of column shift. This same sequence is repeated as many times as the number of steps of column shift to be effected. For instance, if eleven steps of column shift are to take place, then the sequence is repeated eleven times. It

will be understood that if the original amount has, say,

28 digits, eleven steps of column shift, to the right, will drop out the eleven right-hand digits, leaving seventeen of the original digits `in positions displaced eleven places to the right of their original places.

After completion of the desired number of steps of column shift, the amount remaining in the denominational shift unit and manifested by the selectively reversed triggers ASH is read out to the respective Internal Out bus columns. For this, only those triggers ASH which are in reversed status, condition related output tubes OTS, 4, 2 and 1. A positive read out signal SHRO is applied, after completion of the desired number of shift steps, to the tubes OT to render the conditioned ones only of the tubes OT conductive. In this manner, the amount now in the column shift unit is read out, in its binary decimal form, as decreased potentials selectively applied to the buses 8, 4, 2 and 1 in respective columns of the Internal Out bus columns.

.The number of steps of column shift is determined by increased potentials selectively applied (Fig. 15a) to lines MN1, 2, 4, 8, 10 and 20 of the internal commutator of the denominational shift unit which in turn set the descending type electronic counter, units and tens orders, with the amount of shift as described below, said counter being described and claimed in Patent 2,500,294 issued March 4, 1950 to B. E. Phelps. Briefly, this counter has a complete units order of triggers T1, 2, 4 and 8 (Fig. 15a) and a partial tens order comprised of triggers T10 and T20. The column shift amount may be referred to as the minuend and the tens order entry can not exceed -2-. Since any number up to 49* can be entered in the units order, the maximum number of column shift steps is 29. As described in detail in said patent each trigger in the counter is supplied with three tubes which control the application of a binary decimal 8 bit to the trigger. For instance, trigger T1 (Fig. 15a) has its terminal c coupled to the plate of a pentode S-SHCl and its terminal f coupled to the plate of a pentode 7. The control grid of 7 is connected to the plate of a triode 13 While the control grids of S and 13 are connected to the line MN1. Subsequent to the selective application of increased potentials on the input lines MN, a positive going timing signal Ink is applied to the Suppressors of the pentodes 5, 7 and other similar tubes, relating to the other triggers of the descending counter. Assume, for instance, that line MN1 is at in creased potential. Accordingly, the application of a timing signal renders 13 and 5 both conductive. Since 13 is conductive, it keeps 7 in a non-conductive condition. Since 5 becomes conductive and 7 remains non-conductive, the trigger T1 is reversed. In this manner a binary bit of value 1 is applied to the descending counter. Sirn ilarly, tubes 9, 11 and 13a may serve to apply a binary bit of value 2 to the trigger T2 while tubes 15, 17 and 19 may .serve to apply a binary bit of value 4 to the trigger 14 and tubes 15a, 21 and 23 may similarly serve to apply the binary bit of value 8 to the trigger T8. Tubes 25, 29 and 31 pertain to the tens order and function to apply binary bit of value l in the trigger T10 thereof while the tubes 25a, 33 and 35 may serve to apply a binary bit of value 2 to the tens order trigger T20 which, as stated above is the highest binary bit value that may be entered in this order. The tubes 7, 11, 19, 23, 31 and 35 function as blocking tubes to prevent reversal of the associated triggers if a binary bit is not to be applied to these triggers. For instance, if the amount to be entered does not contain the binary bit 4 in the units order, the tubes 15 and 17 remain non-conductive. With 15 nonconductive, it conditions 19. Accordingly, the timing signal Ink will render 19 conductive to block reversal of trigger T4. Such blocking action is necessitated by the interconnections between the triggers. At this point it may also be stated that when the units order of the counter is at 0, the line ZU (Fig. 15a) is at increased potential and thus renders a tube 2a conductive to block the reversal of trigger T2. Such blocking action must be inhibited during the application of a minuend to the counter inasmuch as such minuend may include the binary bit 2 in the units order. For this reason, a triode 16 has its plate coupled to the line ZU and its control grid connected to the line upon which the signal Ink is applied. This signal will render 16 conductive so as to insure the presence, at the time, of a decreased potential upon the line ZU. The tube 2a will thus become non-conductive and will be ineffective to block reversal of trigger 2 during the application of the minuend to the descending counter.

For each step of column shift, the descending counter will be driven one step in a descending count sense. The stepping of the counter is edected by negative entry pulses coming from a tube 2 which is operated as described presently. Each entry pulse is applied to the both sides of the trigger T1 in the units order. Hence, thetrigger will be shifted in response to each such entry pulse. As one specific example, assume that the minuend 17 has been applied to the descending counter, seven being applied to the units order and one to the tens order. Hence, triggers T1,V 2, 4 in the units order and T10 in the tens order are in reversed states, prior to the application of count down entry pulses. The iirst count down entry pulse returns trigger T1, leaving 6 standing in the units order. The second entry pulse re verses trigger T1 which thereupon applies a negative pulse to both sides of trigger T2 causing it to return to the shown status. Since triggers T1 and T4 are now in reversed status, the units order stands at 5. The third pulse returns trigger T1, leaving 4 in the units order. The fourth pulse again reverses trigger T1 causing it to effect reversal of trigger T2. As T2 reverses, it applies a negative pulse to opposite sides of trigger T4, returning it to shown status. Since triggers T1 and T2 are now in reversed status the units order stands at 3. The fifth pulse returns trigger T1 leaving the units order at 2. The sixth pulse again4 reverses trigger T1 which causes trigger T2 to return. Since trigger T1 now is the only reversed trigger in the units order, the units order stands at l. The seventh pulse restores trigger T1 and the units order then stands at 0. It is seen that the ap- I plication of seven entry pulses has stepped the units order, descendingly, from its initial 7 status to its 0 status. With the units order in .0 status, thetubes 8a, 12a, '20a .-and.24a vare all'heldnon-.conductive vbyfthe related triggers 1, 2, 4 and 8. Accordingly, the common output line ZU of these tubes is at .increased potential. 'The increased potential on line ZU is applied to the suppressor of a tube 14, also to the control grid of a tube Y28, and to the grid of the tube 2a. 'In response to the increased potential, tube 2a becomes conductive to block trigger T2. The eighth count down entry pulse applied to the 4descending counter reverses trigger T1. Inasmuch as trigger T2 is now blocked, the reversal -of trigger T-1 is ineffective to reverse trigger T2. As the trigger T1 reverses, it acts through a suitable coupling capacitor to apply a positive going impulse to the controlv grid of the now conditioned tube 14. This 'tube accordingly becomes conductive and reverses trigger T 8. The Atriggers T1 and T8 are now in reversed status, so that the units order stands at 9. In otherwords, the units order, when at'O, is stepped by the next entry pulse to '9, as is required of a descending counter. It is further required that upon the units order being stepped from O to 9, a subtractive carry of l be 'eiected into the tens order. Trigger T8 reverses only when the units order steps from Oto 9. Upon its reversal, trigger T8 applies a negative pulse to both sides or trigger T10, causing 'it to vshift in status. Since the trigger T10, in the assumed example, was previously in reversed status, vthis carry pulse from trigger T8 causes the trigger T10 to vreturn to the shown status. Since both :triggers T10 and T20 ofthe tens order are now in reset status, the .tens order stands at O. The related tubes 32a and 36a are then nonconductive and their common anode line ZT is at in creased potential which is impressed on the suppressor of tube 28. The descending counter now stands at 9, having been stepped descendingly from its initial .17 status to its 9 status in response to 8 .successive entry lpulses. The ninth count down entry pulse 'returns trigger T1 and the counter then stands at 8. The tenth entry pulse turns trigger T1 causing it vto turn trigger T2. As trigger T2 turns, it reverses `trigger T4. Upon reversal of trigger T4, it resets 'trigger T8. Thus, the triggers T1, 2 and 4 are now in reversed status, so that the counter stands at 7. It is seen that -ten entry ,pulses have effected a descending value cycle of the units order from its initial 7 ,status back to a 7 status. ing this value cycle, as the units order stepped from to 9, it leffected a subtractive carry of 1 from the tens order.

-In a manner now clear, seven more 'entry pulses I,will bring lthe units order `to 0 status. Thereupon, line ZU goes to high potential, which is impressed "on 'the lcontrol grid of the Itube v28, previously-conditioned lbythe line ZT under control of the tens order in"0 status. The 'tube 28 thus becomes conductive when the descen'dling'counte'r'is at zero and applies decreased potential -to Atube 16a, causing output lline F to rise in potential. This brings about termination of column shifting, in a manner described below.

'The operation of the descending counter has ybeen explained above. The minuend, which is Yindicative "ofllthe column shift amount, is `'applied to tubes in the -descending counter lprior to the application of the positive entry signal lnk. This lnk signal comes from the plate 'of va tube -SHC2 (Fig. 15b). The main sequence means operates at the proper time -to apply a negative signal lnk tothe grid of this tube 5 which thereupon produces the positive ink signal, as la result of which the lcolumn shift amount is entered into the triggers of the descending counter, as described above.

The direction of shift is determined by increased potentials applied to the proper circuits. If the shift is to be to the left, increased potential is applied 'to line LT (Fig. C), but if the shift is to be to the right, then increased potential is applied to line RT. Increased lpotential on line LT conditions 9-SHC3 (Fig. 15C), while increased potential on line RT conditions 17.. Subsequently, the positive signal ink renders only the conditioned one of the tubes 9 or 17 conductive.- If 9is rendered conductive, it turns trigger 2-1 to the left (its terminal c goes to low potential) and if 17-is conductive, `it

turns 21 to the right (its terminal f goes to low potential).

lf 21 is in its left status, it cuts on1 25a, which is `a condition for production of the left shift signal LSH atthe proper time. If 21 is in right status, it cuts oi 25 which is a condition for production of the right shift 'signal yRS Also, dur- 4 `The column .shift means'has its own oscillator nand amplifier source of'SO kc.,ipiils"es And B, .yvhicha'repl'SO degreesout of 'phasewith each other, 'as indicated inFig. 15b.

After entry of the column shift lamount intoi'the descending counter, a negative signal SHCLy isproduced which (Fig. 15b) cuts 'olf 21-'SI-C2. Tube -21ftlhereupon applies a positive signal SHCL to the s'tandard'SHC cancel circuit (Fig. 15C). The output 'of the cancel circuit resets those triggers, in a manner as described-above (except the triggers in `the descending counter) in ythe internal commutator of the denominational shift means which are marked with the reset status symbol x. The triggers in the descending counter (Fig. 15a) 'are in the shown states when the counter is at zero. This counter, however, isvreset to vzero by the column shifting operation described below.

The positive signal vSHCL is also applied to ytheg'rid's 'of 38 yand 36 in Fig. 15C. 'In response, 38 cuts off 38a,"to turn 39, which then applies,through a capacitor, `apositive impulse to 36a which, -in turn, 'through a capacitor, 'cuts oif 4i). Tube 40 4then causes P40 to produce the "first negative cancel signal ACL which, as stated above, is impressed on all the triggers ASH of the shift columns (Figs. l2 and. '13). The positive signal SHCL is of short (one AP pulse cycle) duration. When this signal terminates, 36 and 3? become non-conductive. As '3'6 becomes non-conductive, it resets trigger 39. It is clear that the first cancel signal ACL for the shift columns is produced under control of this signal SHCL.

Concurrently produced with signal SHCL, the negative signal 'SHRI cuts off 25a (Fig. 15b). Tube I`25a then renders a tube 2S conductive to cause a power amplifier 'P25 to produce the positive ,going entry SHR u signal which, as stated above, is applied to the shift columns to eir'ect the entry of the number from the In ternal In bus column into the shift columns (see Figs. l2 and 13).

The apparatus is now ready for column 'shifting the number which has been read into the shift columns, lThe column shift is initiated by a negative start signal SHS (Fig. 15C) produced at the termination of the'SHRI'readin or entry signal. This SHS signal has a Vchance time relation to the 5() kc. A and `-B pulses continually produced by Athe SHC oscillator andarnplitier (Fig. 15b). I

lFig. .14 :is a timing chart vof pertinent operations which are initiated yby the SHS signal and 'covers specifically the .example of a column shift'amount of 3 entered into the descending counter (Fig. 15a) as will now be described.

This :negative start signal :SHS is applied to the control .grid of the normally conductive tube yS-SI-IC3 `(Fig. 15e) and also to the terminal g of a trigger 6. This lsignal cuts oi 5, forcing 6 to reverse. The signal is of short duration and -at its termination the l-ine carrying the signal returns to high potential and thereby restores '6. Meanwhile, while 6 was reversed it in -turn reversed 11, as indicated Vb y the 4heavy black line labeled 11-SHC3 in Fig. 14. The 'time of reversal of 11 is an indication of the time of occurrence yof the start 'signal SHS. Upon this lre'versal of `11, it conditions 12 (Fig. 15C) to become conductive in response to the next B+ pulse, thereby to reverse 15, as shown in Fig. 14 by the heavy black line flabeled 15-SHC3- Reversed 15 cuts off 14a. At present, '31a also is cutoff, so that the lock couple 31a+14a is leffective to condition 35 to respond to the next A+ pulse. This next pulse causes A35 :to apply, through a capacitor, a negative pulse to 34 cutting it off, vwhich makes 'P34 conductive 'to produce the negative BCL signal, as indicated by the similarly labeled black line in 14. A's stated above, this is t-h'e first signal in the 'sequence of four signals occurring in each shift step, per s e. BCL resets 'triggers BSH of each shift column (see Fig, l2), as previously stated, preparing them to receive a right or left shifted digit. When 15 was reversed at the B+ time to cause the BCL signal to appear at the next A+ "time, it also conditioned 16 (Fig. 15C) to respond to A+ pulses. The negative pulses thus 'produced The first A+ pulse turns 20 which thereupon cuts off 23a to condition 22 to become conductive with the next B+ pulse. When ZZ becomes conductive, it cuts off 26 andu26a. Aspexplained before, if a right shift has been called for, trigger 21 is in 'right-shifted position and H. 8 5 cuts en :25. But, if a left lshift has been call-'ed for, then 21 is in left-shifted condition and cuts olf 25a. Accordingly, when 26 and 26a are now cut olf under control of 22, either lock couple 26-2S or 26a-25a becomes fully cut off, depending on whether a right or left shift is to be performed. lf 26-25 is cut off, it works through 33 and P33 to produce the positive RSH signal (Figs. 15C and 14) while if 26a- 25a is effective, it operates through 29 and P29 to produce the positive LSH signal. As s tated above, the signal RSH or LSH (Fig. 12) respectively, causes the right or left shifted digits to be entered in triggers BSH of the shift columns.

When 22 (Fig. 15C) became conductive at the first B+ time in the lst shift step, it caused the shift signal LSH or RSH to be produced, as just explained. It also reversed 19 which, in turn, reversed 18. With 19 reversed it cuts olf 28 to make 31a conductive so that lock couple 31a-14a will be ineffective and the next A+ pulse will not cause a BCL cancel signal to appear. lnstead, an ACL cancel signal will be produced which is subsequent to the ACL signal produced at the same time as SHRI, as described above. This results from 28 conditioning 32 to respond to the next A+ pulse. Thereupon, 32 applies, through a capacitor, a negative pulse to 4i) as a result of which P40 produces this negative ACL signal (Figs. 15e and 14). This signal, the third in the sequence of the four signals appearing in each shift step per se, resets triggers ASH of each shift column (see Fig. l2), preparing these triggers to receive the shifted digits now temporarily stored in triggers BSH. Successive ACL signals are produced by the internal commutator of the column shift means, in the manner just described.

At the A+ time at which this ACL signal is produced (Fig. 14) 16 (Fig. 15C) responds to an A+ pulse and restores 20. Thereupon 20 cuts off 31 and 23. As 31 is cut off, it produces a positive pulse which is transmitted via line C (Figs. 15C, 15b and 15a) to tube 2SHC1. In response to this pulse, tube 2SHC1 produces a negative count down entry pulse which as described above, steps the descending counter to diminish its count by l. As the descending counter in the assumed example of Fig. 14 started at 3, it is now stepped to a count of 2 (see Fig. 14). In this manner the descending counter is operated in each shift step to reduce the count by l each time.

The iirst three signals, in the 1st shift step per se, have been produced in the manner just explained. These first three signals are, namely, BCL at the A+ time in the shift step (Fig. 14) LSH or RSH at the succeeding B+ time, and ACL at the following A+ time. The fourth and final signal in the sequence for each shift step per se is the SHE signal which is produced at the B+ time following the ACL signal. The SHE signal will cause the shifted digits to be transferred from triggers BSH to ASH. lt was explained above that 26-SHC3 (Fig. 15C) was restored by the second A+ pulse in the shift step and thereupon cut off the tubes 31 and 23. The tube 31 thereupon caused the descending counter to diminish the count by 1. The tube 23, when cut off, conditions 24 to become conductive with the next B+ pulse. When 24 becomes conductive it cuts o 27. Tube 27a has already been cut off by the previously mentioned reversal of trigger 1S (also see Fig. 14) which will not be restored until the end of the last shift step. Accordingly, when 24 cuts off 27, the lock couple 27-27a is effective to make 30 conductive and thereupon cause P30 to produce the SHE signal. This signal SHE, as previously stated, causes the shifted digit to be transferred from temporary storage triggers BSH (Fig. l2) of each shift column to triggers ASH of the same shift column. This will complete one step of shift.

The same sequence of signals BCL, LSH or RSH, ACL and SHE, along with a step of descent of the descending counter to l, in the example assumed, is repeated in the 2nd shift step. A 3rd shift step then takes place in which this same sequence of signals is again produced and half way in this 3rd shift step the descending counter is stepped to 0. As previously described, when the descending counter is at 0, the tube 16a-SHCI (Fig. 15a) applies increased potential to the line F (Figs. a, b and c). The increased potential on this line renders 8a-SHC3 conductive to restore 11 (Fig. 14). With 11 restored, it conditions 1t) to operate in response to the next B+ pulse to restore 15 (Fig. 14). l/Vth 15 restored, it conditions 13 to become conductive with the next A+ pulse and thereupon to restore 18 (Fig. 14). It will be noted that 18 is restored at the termination of the SHE signal (Fig. 14) in the last shift step. All the triggers 11, 15, 20, 19 and 18 are now in reset status and the shift steps are terminated. I

ln the foregoing manner, when the column shift amount is assumed as 3, three shift steps are produced. Similarly, any other number of required colurrm shift steps are performed, the number of such steps being determined by the column shift number applied to the descending counter.

At the termination of the steps of column shift, the shifted number in the denominational shift unit (Fig. 12) is to be read out upon the corresponding Internal Out bus columns. As already explained, 18-SHC3 (Fig. 15e) was restored at the end of the last shift step. As 18 restores, it applies a negative going pulse to 14 causing 14 to apply a positive going pulse by way of a line 14w (also see Fig. 15b) and a capacitor to the control grid of the normally conditioned tube 39-SHC2. Accordingly, 39 becomes conductive and turns the trigger 40 (Fig. 15b). As 40 turns, it makes 36 conduct to produce a negative going shift complete signal SHCP. This signal is utilized to produce a negative read out signal SHRO which is applied to 32-SHC2 (Fig. 15b) cutting it off. Thereupon, 35a becomes conductive and restores 40. Also 35 becomes conductive and acts through P35 to produce a positive going SHRO signal. As described before, this SHRO positive signal (Fig. l2) causes the number stored in the triggers ASH of the shift columns to be applied to the buses of the associated Internal Out bus column.

When the column shift amount is 0, and a number is entered from the Internal In bus column to the denominational shift unit, it will be read out of this unit to the Internal Out bus column with no column shift. When the denominational shift amount is 0, the descending counter (Fig. 15a) maintains line F at increased potential to condition a tube 7-SHC3 (Fig. 15e). Then, when the start signal SHS turns trigger 6 (Fig. 15C) the trigger applies a positive pulse through a. capacitor to the conditioned tube 7 to render it conductive. The output of this tube is applied via a Wire 7w (see also Fig. 15b) and the anode resistor of 39-SHC2 to the trigger 40, turning this trigger. The effect of this is to cause the shift complete signal SHCP to be produced, in the manner just explained above. Consequently, the read out signal SHRO will be produced, causing the number read into the denominational shift unit to be read out, without a column shift. Novel means have therefore been described for producing a selected number of steps of column shift and in a desired direction by electronic means which are inherently fast in operation whereby the requisite number of column shifts can be performed at extremely high speeds so that the overall speed of a series of computation steps can be greatly increased.

While there have been shown and described and pointed out the fundamental novel features of thek invention as applied to a single modification, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

l. A digit shifting circuit for shifting a digit from one order to another, each order comprising digit storage means and shift control means, circuit means coupling the digit storage means of a given one order to an associated shift control means allocated to another order whereby said shift control means is selectively conditioned in accordance with the status of the connected storage means, means applying a shift producing energy change to all said shift control means, and means respectively connecting the shift control means of a given order to the digit storage means of another order whereby the digit stored in a given order is shifted under control of said energy change to the storage means of another order.

2. A digit shifting circuit for shifting a digit from one order to another, each order comprising a plurality of digit storage means, shift control means, circuit means coupling the digit storage means of one order to the associated shift control means allocated to the other order whereby said shift control means is selectively conditioned in accordance with the status of the connected storage means, means connecting the shift control means coupled to one order to the digit storage means of another order,

lf3 y and. means `for Iapplyinga.shift producing ,energy changexto all fsaid shift @contro '.rneais lwherebytlie digit-.stored in meerder ieshifd 't' aqttteeqfner.

v3.y A digit shift'ing .circuit for ,shifting a .digit from one order to ',another, each ,order ',colmprising electron ,valve triggertype digitfstorage.meanganelectron gatefcontrolled bythe .status `lof Aa triggeniri. one order andconnected toa triggerin another order, nieansapplying Iashift,producing energyl changefto .all said gates whereby the ,digit Ustored in one orderis fshiftedlto'aiother .order, each.order com- Prisme a Pluflfvof gaislftrggfartypg ,Storage means., .said triggers lineach order beingless in v,number thantheradix employed. 1

4. Adigit shifting circuit .for y.,slgiif-tling a .digitfrom one order'to.anoteriach v der h n d i triggerfvpe-diglfst" s,.a1.le,ctr0ngate ,Controlled by the statusfof la, rig another order, ytrigger means gonnctd' t0 Saidgate". 'femegigt gaia gate and the trigger 'Stora' e meansof order, forintermediate storage of a .digitzreprese 't n' and l.means applying ya shift producing 'energy ,change to all VVsaid gates whereby the digit'storedlin lfone @order Iifs ehifted to said intermediate triggerV iea Rrepagtory .to ,transfer t0 vthe trigger storage means of ,its order.

' 5. Adigit shifting circuit for-shifting a digitfroin ,one order to another, each order comprising electron valve trigger type digit storage means, an lelectron gate controlled by the status Kof a trigger in vone order and connected to a trigger in `another order, means applying a Shift Pfodlcing energy .Change .t0 .all tsaid gates whereby lthe .digit stored in one order i s shifted to another order and means inclu'dingsaid gates for ,controlling the direction of shift' of afdigit''stored in any order, selectively, to either the right orto the left.

6. A device .as ,claim A5, said gates comprising duplicate gate means in `.eacharder, respetively controlled in accordance with the direction of shift desired.

7. A digit shifting circuitfor shifting .a digit from one order to another, each .order .,Cornprisiing electron valve trigger type .digit Storage means, an electron gate c011- trolled by theV .status of va trigger in one order and connected .to a .trigger inlanotlier order, means applying a shift Vproducingenergy change to .all Isaid gates whereby the digit stored lin one order `-shifted to another order and counter means controlling said shift producing means to produce a controlled number of shift producing energy changes whereby the number of steps of shift is determined by said counter.

8. A device as in claim 7, and means for setting said counter means to a setting determinative of the number of steps to be produced.

9. A device as in claim 7, and means including said gates for controlling the direction of shift, said counter means controlling the number of steps of shift in a selected direction.

10. A device as in claim 4 and duplicate gate means connected to said intermediate storage trigger.

11. A digit shifting circuit for shifting a digit from one order to another, each order comprising a plurality of digit storage means, a plurality of said orders, shift control means respectively connected to each digit storage means, circuit means coupling each of the digit storage means of one order to the shift control means of another order, means selectively operating said digit storage means in each order to represent a digit stored therein, said coupling means selectively conditioning said shift control means in accordance with said represented digit, and means applying an energy change to all said shift control means whereby each selected digit representation in one order is shifted to another order.

12. A shifting register comprising a set of electron valve trigger elements, means for selectively setting said trigger elements to represent a digit, a second set of trigger elements, electron gate means connected to each of said iirst set of trigger elements, respectively, and conditioned selectively in accordance with the individual setting of the trigger connected thereto, means coupling each of said gates to one of the triggers of said second set, means applying an energy change to al1 said gates whereby the selective setting of said first set of triggers is transferred to said second set, said sets of triggers being less in number than the radix employed.

13. A shifting register comprising a set of electron valve trigger elements, means for selectively setting said trigger elements to represent a digit, a second set of mprising electron valve 4 14 trigger elements, .elegtlzantggtc tmeansonpeeted toeagh Qfsaidfrsts `.riggerelements,Arismendi',@dennditionedselect `ely Ain .accordance y.with the .individual setting of the Itriggerconnectedthereto, means coupling eachfsad.getesteone of the triggersoffsaid second set, me'ansapplying gnfencrgy change ,to ausaid gateswherehy the selective setting o ,fisaid ifirst set of `,triggers is transferredto said second set .and a yduplicate set of gates eonnected between saidpiirst `setof .triggers and anotherset.

14. Adeviceas in claim 13, andmeans for selectively rendering one only of said .setsfof .gatesoperative atany one time, to control direction of :shift ,from .one set-of triggers to another.

15. .A shifting register ,comprising fa .set ,of zelectron Valve trigger elements, .means .for selectively setting Lsaid trigger elements vto .represent adigi'f., l .second seto'f Mig ger elements, 4electron ,gate ,means 4connected `.to .each fof said yfirst set .of triggerlelementa respectively, ,and conditioned selectively i accordance .with .the individual setting of the trigger connected thereto, means couplingeach of said gates vto .one of .the triggers gof said second fset, means applying an energy change to all .saidgates where- .,by the selective settingv .of said `first vset of triggers gis transferred to said second set ,and including a plurality of said dual .sets o f triggers, ,and ,counter means ,controlling said energy change ,applying lmeans to control the number .of .times of .application of said .energy changes yin accordance with Lthe ,value .entered `in said counter to thereby control the number of steps of shift among Asaid trigger sets.

16. A .register 1comprising a set .of electron valve trigger elements, means .for individually setting said ,triggerelements whereby the permutation .of settings of said set vis representative of aselected digit, electron gate means, one .connected respectively to each trigger land means effective to control .said gate means and 'sa-id trigger set whereby said first permutation .of settings is replaced y by a separate permutation entered via said gates.

17. A .device as ,in .claim y16, a second'set of trigger elements, means `for individually setting said second set, means respectively 4connecting said second set to said gates, and means whereby said gates are rendered .elective to transfer .the permutation .of :settings 4,of one of said sets. lto the .other-ofsaid sets.

18. A device as in claim 17, cancel means for cancelling the settings of one of said set of triggers and means for rendering said cancel means and said gates effective whereby the permutation of one of said sets is cancelled and replaced by the permutation of the other of said sets.

19. A shifting register comprising a plurality of at least three bi-stable elements connected in cascade each initially respectively storing a binary 1 or a binary O representation of a value, dependent upon which of said bi-stable conditions is assumed, means statically sensing an initial binary 1 or binary 0 condition of one of said elements and means for transferring the binary l condition of any one element to the next one of said cascaded elements as a lateral shifting operation between cascaded elements, including means for applying a change of energy to said sensing means thereby rendered operative only upon such an applied change of energy and its associated storing element being in the binary 1 condition to transfer said binary 1 condition to the next one of said cascaded elements, each binary 1 conditioned element remaining in its binary 1 condition, during said sensing, but operable respectively to either a binary 1 condition or a binary 0 condition immediately subsequent thereto dependent upon the initial binary l or binary O condition of a preceding one of said bi-stable elements whereby the one condition of any one element is transferred to another element and any one element is altered to or retains the binary 1 or binary 0 status of a preceding one of said bi-stable elements.

20. A shifting register comprising a plurality of bistable elements each respectively storing a binary 1 or a binary 0 respresentation of a value, dependent upon which of said bi-stable conditions is assumed, means statically sensing a binary 1 or binary 0 condition of one of said elements and means for transferring the binary 1 condition of said one element to another of said elements, as a shifting operation, including means for applying a change of energy to said sensing means thereby rendered operative only upon such an applied change of energy and its associated storing element being in the binary l condition, to transfer said binary 1 condition to another element, said first element remaining in its binary 1 condition, during said sensing, whereby the one condition of said rst element is transferred to said other element and said first element remains in its one condition, during the initiation of said shift operation and including means for transferring said binary 1 condition, selectively, in either one of two chosen directions.

21. A device as in claim 20, each of said elements including means providing an additional transfer output and including means for transferring said binary 1 conditions via said additional output.

22. A digit circuit for shifting a digit from one order to another, each order comprising a dual stability storage means, means statically sensing the setting of one order without altering its state and connected to another order, and means applying a shift producing energy change to said sensing means, whereby a digit stored in said one order is shifted to said other order and including means for controlling the direction of said shift, selectively, in one direction or another.

23. A device as in claim 22, each of said dual stability means including means providing an additional shift output and including means for shifting said stored digits via said additional output.

24. A shifting register for shifting data from one unit to another comprising in combination at least, two dual stability storage units and at least one transfer unit, said transfer unit comprising means for statically sensing the condition of one of said storage units without altering its status, selective transmission means, for receiving an applied change of energy, including said transfer unit, connected between said storage units, to statitically sense the status of said units and to transmit an energy change supplied thereto, only under a predetermined status of said unit being sensed and including means for transferring said energy changes selectively, to either one or the other of said units, from either the other or said one, respectively.

25. A device as inv claim 24 and including means for transferring the data in said units simultaneously out of all of said units without alteration of the state of stability existing in said units.

26. In binary digital computing and counting apparatus the combination of at least two multivibrator storage units and at least one transfer unit; said storage units each having two oppositely designated output terminals and a triggering input terminal, and having .two stable states of conduction; said transfer unit comprising a multiterminal potential sensing and selective transmission network having at least two sensing terminals, an input terminal for receiving triggering voltage pulses, and an output terminal for transmitting said voltage pulses; said transfer unit being interconnected between said storage units to sense through said sensing terminals the potentials of two of said storage unit output terminals, and to transmit triggering voltage pulses supplied at said transfer unit input terminal to said transfer unit output terminal only under predetermined relations of the sensed potentials.

27. A transfer unit, comprising a multiterminal potential-sensing and selective transmission network having at least two sensing terminals, an input terminal for receiving voltage pulses, and an output terminal for transmitting said voltage pulses, said transfer unit being interconnected by said sensing terminals between a pair of double-valued voltage sources to sense the potentials of said sources and to transmit a voltage pulse received at the input terminal thereof to the output terminal of said unit only if the voltage values of said sources are in a predetermined relationship.

References Cited in the le of this patent UNITED STATES PATENTS 2,404,047 Flory July 16, 1946 2,435,840 Morton Feb. 10, 1948 2,666,575 Edwards Jan. 19, 1954 OTHER REFERENCES First Interim Progress Report on the Physical Realiza- 

